Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Board » Technical Support » distance to go

Page: Previous 1 2

Posted by
Olive


Users avatar

Posts
4
Registered at
2012-12-24 20:22:03
2012-12-30 09:18:14 - Re: distance to go
That's all indifferent since the nonsense numbers lead us all astray. Who cares if it all makes sense when we "get close." Why play along at all. Sheeeze...
Posted by
RainbowChaser


Users avatar

Posts
2656
Registered at
2009-06-14 09:44:50
2012-12-30 09:22:52 - Re: distance to go
evilonod - I can sympathise with your frustration, but rest assured there is no-one getting any advantage here. It really is all about the shape of the globe and how SOL's calculations are made.

Please don't give up on us!
Posted by
hmm


Users avatar

Posts
118
Registered at
2011-11-03 13:35:22
2012-12-31 10:06:10 - Re: distance to go
I believe I have now found the root cause of this problem. I have described it in my blog:

http://blog.sol.hmm.iki.fi/2012/12/scoring-problem-on-races-crossing-idl.html
Posted by
outlaw


Users avatar

Posts
33
Registered at
2012-06-01 13:37:55
2012-12-31 17:07:52 - Re: distance to go
As for the DTF calculations, how about simply calculating GC bearings to the next couple waypoints, then using GC distance to the best WP based on bearings + rounding direction. I suspect this may lessen server load as well. (see pic)
Attachments
Posted by
hmm


Users avatar

Posts
118
Registered at
2011-11-03 13:35:22
2013-01-02 11:45:03 - Re: distance to go
I have also tried to explain the DTF calculation in more detail in my blog, check the post here:

http://blog.sol.hmm.iki.fi/2013/01/dtf-calculation-problems-near-polar-area.html

As I say in the post, the DTF calculation is run every 15 seconds for each boat, so changes to that code have to be made very carefully not to cause the server too much load.

However, that doesn't mean that there will not be improvements in the future. It just means that the changes have to take into account also other things than only always getting the best possible DTF for the boat.
Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2013-01-02 14:26:49 - Re: distance to go
Is it not possible for each player (sailor ?) to merely run the measuring caliper tool, in Great Circle mode, between the next turning mark and the current position of any boat (including his own) in which he has an interest?
I just do not understand the cause of all this worry over such a trivial problem.
Congratulation to Markku H. for solving the causes of the SERVER'S problem, but it is really not a problem to the SAILOR.
If it breaks, it's not strong enough--if it doesn't, it's too heavy.
Posted by
outlaw


Users avatar

Posts
33
Registered at
2012-06-01 13:37:55
2013-01-02 18:32:12 - Re: distance to go
> the DTF calculation is run every 15 seconds for each boat

This is unneeded, do a proper distance calculation every 16 steps, and use increments (VMC * timestep) inbetween.

That means only one in 16 boats gets a full calculation for a given timestep.

The same could be done for roundings, maybe.

--- Zuletzt bearbeitet von outlaw am 2013-01-02 18:33:23 ---
Posted by
hmm


Users avatar

Posts
118
Registered at
2011-11-03 13:35:22
2013-01-02 19:25:05 - Re: distance to go
To do that the VMC (and the course which to calculate VMC for) should be calculated for each boat every 15 seconds so it's not clear if it's easier to it that way.

The VMC, VMG etc numbers you see at the client are calculated at in your own computer and are thus "cheap" for the server but on the other hand are not available there directly.

It's good to have different ideas how to improve the calculation but as Rod wrote earlier I don't see it as a major problem now.
Posted by
Hasseballad


Users avatar

Posts
17
Registered at
2008-11-15 11:51:32
2014-05-25 07:33:33 - Re: distance to go
Recent experience at RTW2014-leg4. The "rounding line" ref. hmm for Cape Horn has a limit at 83S & 34W. Why not move that limit to say 65S & 64.2W or the exact W pos. on the "rounding line". Wouldn't that be a simple improvement for the boat position at the Horn specificly.

Rgds Hans

Page: Previous 1 2

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Guess Gotland TIMED Race 2026

The Guess about Gotland is do we helm our First 27 solo east or west of the island in this 140 nm race. This is a TIMEDrace so you may RE-REGISTER HEREto try again after finishing a run. You will have 13 days and 11 hours to test your skill and decision making after the race opens.
Race #2030
INFOby brainaid.de
First 27 solo Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ2 - TRCH - SYC
RACE CLOSE: Saturday,
2 May at 23:00 UTC
Race starts: Apr 19th 12:00 Registration will open soon
▶ Flash
GO TO RACE

Quiberon Islands 2026


The Quiberon peninsula extends as a submerged granite ridge a further 15nm or so beyond the La Teignouse lighthouse on the rocks off its southern tip, surfacing as two small islands, Houat and Hoedic, the duck and duckling in Breton, 5nm and 10nm beyond the light. Treacherous, tidal waters, but on SOL that daunts us not. Of course, we've raced here before, mostly Timed Runs out of Quiberon around Belle Ile, just south of the islets, and back, but this time it's a sprint from Belle Ile's capital of Port Marie round the foul fowl and back. A triangular course of 22nm, appropriately enough for Moody S38.
Race #2022
INFO by brainaid.de
Moody S38 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
RANKING:
SPQ2-SPCH-SYC
RACE CLOSE: Tuesday,
April 21 at 2300 UTC.
Race starts: Apr 18th 02:00 Registration Open!
▶ Flash
GO TO RACE

The Three Kings Race 2026


The Three Kings Race returns with a demanding 468 nautical mile challenge from Auckland up to the remote Three Kings Islands and back again. This rugged and spectacular course tests both endurance and strategy as our SOLers navigate open ocean and ever-changing conditions. Racing the powerful Riptide 50, our SOLers will need precision, timing, and smart routing to master this iconic out-and-back course and secure a strong result!
Race #2028
INFO by brainaid.de
Riptide 50 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SUPBUD - SYC
Race starts: Apr 16th 22:00 Registration Open!
▶ Flash
GO TO RACE

Roma per Tutti 2026


Sailonline are honoured and delighted to have been asked to partner an online first Roma per Tutti yacht race with organizing yacht club, Circolo Nautico Riva di Traiano . In real life, this will be the 33rd edition of this 540nm offshore race from Rome’s Riva di Traiano to the Aeolian Islands and back. Online, the race will not only be our first partnership with CN Riva di Traiano, but also the second race of our Magical Mediterranean series. A number of Mini 6.50s have been entered for the 33rd edition of the Roma per Tutti; so our own vintage Mini is also our virtual yacht of choice for this one.
Race #2019
INFOby brainaid.de
Mini 6.50 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: MED - SUPBUD - SYC
RACE CLOSE: Wednesday,
April 22 at 2300 UTC.
Race starts: Apr 11th 10:00 Registration Open!
▶ Flash
GO TO RACE

Rommel by Balloon 2026 - Through the Sahara


Generalfeldmarschall Johannes Erwin Eugen Rommel may have been that chivalrous, gallant tank commander of legend, led astray by the Prussian military traditions of loyalty and chain of command, but one thing he wasn’t, was mad. So, let’s do it anyway – not stick to the coast and the battle for logistical superiority – but depart the oases of Siwa south west into the desert for Agadez and its uranium. And let’s go by balloon, it’s only 2500km (1250nm)!
Race #1973
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: BOL - SYC
Race starts: Apr 07th 13:00 Registration Closed
▶ Flash
GO TO RACE

Falklands to Tasmania 2026

Welcome to yet another all-new route. This next race is part of our Ocean Championship as well as the ROW series. Falklands to Tasmania, is like last year's island to island. It’s one of the longer ones 6400nm, more than half way around the world (and the Antarctica). It starts the 2026 OCQ2, and will be sailed in our Steinlager 2, contrary to prior notice.
Race #2021
INFO by brainaid.de
Steinlager 2 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ2 - ROW - OCCH - SYC
Race starts: Apr 06th 11:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member KaSToR
  2. Sailonline Yacht Club Member WRmirekd
  3. Sailonline Yacht Club Member rafa
  4. Sailonline Yacht Club Member rumskib
  5. Sailonline Yacht Club Member CriticalHippo
  6. Sailonline Yacht Club Member Panpyc
  7. Sailonline Yacht Club Member CollegeFund
  8. Sailonline Yacht Club Member Sax747
  9. Sailonline Yacht Club Member sassy63
  10. Sailonline Yacht Club Member vida

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client